The so-called "contraception mandate" of the health-care law requires employers to provide in their health insurance policies preventive services for women that include access to contraception and sterilization.
The court will hear two consolidated challenges brought by closely held companies and their owners.
One of the cases was filed by arts-and-crafts retailer Hobby Lobby Stores and Mardel, a chain of Christian bookstores. Both are owned and operated by David and Barbara Green and their children, who are evangelical Christians. The other case was brought by a Mennonite family that owns a company in Pennsylvania, Conestoga Wood Specialties. The company is owned and operated by Norman and Elizabeth Hahn and their three sons.
Freedom of religion
The justices will weigh whether the challengers have a claim under a 1993 federal law called the Religious Freedom Restoration Act (RFRA) and the First Amendment to the U.S. Constitution, which ensures the free exercise of religion.
The case, which has no bearing on the broader fate of the health-care law, will determine whether some companies will be exempted from the contraception coverage requirement. Religious institutions already are exempted from the regulation.
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In court papers, some Republican members of Congress have supported the companies, while Democrats have backed the Obama administration.
The administration's lawyer, Verrilli, said in court papers that a victory for the companies could lead to a series of similar challenges to other federal requirements, potentially including objections to minimum-wage laws, Social Security taxes and anti-discrimination laws. He noted, for example, that a company could object to providing health coverage that includes vaccinations.
"A reading of RFRA that would produce this regime of virtually automatic exemptions from critical employee-protection legislation cannot be correct," Verrilli wrote.
The government is backed by women's rights groups, who say contraceptives should be made as widely available as possible for public health reasons.
The challengers and their supporters, including a wide-range of religious groups, counter that the case is really about whether the government can trample on fervently held religious beliefs.
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"No one should be forced to give up their constitutionally protected civil rights just to go into business," said Kyle Duncan, a lawyer for Hobby Lobby.
The cases are Sebelius v. Hobby Lobby and Conestoga Wood v. Sebelius, U.S. Supreme Court, No. 13-354, 13-356.